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James Wonnacott wrote: > > Actually I read the other day that where ever you are there is usually > at least one rat within 20 yards!!!!!! Land area of UK - 241,590 Sq Kilometers. Sq Kilometer is a 1000,000 square meters. Within 20 yards suggests a rat population around 200 million if my back of the envelope calculation is correct. Assuming (very unrealistically that rats spread themselves out in a very efficient hexagon grid system in order to make the figures work). The BBC is claiming a rat population of 60,000,000, which suggests that 20 yards is a tad low, of course the area covered increases as the square of the radius. So I make that about 35 meters (not yards, or chains, for furlongs), with optimum rat coverage. Of course if the rats all stayed spaced out that far, they would never be able to breed. I'm not sure how to correct the figures for distribution, I think you'd need to know how clumpy rat populations are, but I bet the net result would be that most of the time, most people outside densely populated residential areas are well away from wild rats. Which concurs with the claimed housing studies saying only 1.7% of houses have rats outside (however that was defined, 0.4% rats inside). I'm also cynical of the 60 million figure. It was estimated at 40 million at the turn of the century, and I'm pretty sure that rural small mammal populations have declined dramatically since then (water voles, dormice etc are all scarce little creatures these days. I doubt the rural Brown rats escaped), and my experiences with the Norfolk barley harvest concurs with the view that the rural rat is pretty scarce. Of course it is possible the urban rat has replaced these losses. - The Mailing List for the Devon & Cornwall LUG Mail majordomo@xxxxxxxxxxxxx with "unsubscribe list" in the message body to unsubscribe. FAQ: www.dcglug.org.uk/linux_adm/list-faq.html